Autosomal dominant Stargardt-like macular dystrophy (ADSLD) is an early-onset form of macular degeneration. ADSLD is one of several heterogeneous causes of macular atrophy in association with subretinal deposits that leads to blindness. ADSLD is of particular interest because of the mutated gene's important role in macular function and phenotypic overlap with age-related macular degeneration (AMD). The long-term goals of this research are to better understand the etiologies and pathophysiologies of macular degenerations. Macular degenerations and dystrophies are common causes of blindness worldwide and the leading cause in older Americans. Heredity plays a major role, not only in the early-onset forms, but also in the more common later-onset macular degenerations. There is no effective treatment for the vast majority of patients. The study of early-onset hereditary macular diseases, such as ADSLD, will provide new knowledge of retinal function and an improved understanding of the pathophysiology of hereditary macular degeneration. The immediate goals of this application are to test the hypothesis that patients with ADSLD linked to chromosome 6 are related through a common founder by genetic and genealogical investigation; to identify and characterize the ADSLD gene; to begin to understand its sites of expression and function; and to determine if the ADSLD gene is involved in a proportion of late AMD.